They eat deer. Fawns... full grown... doesn't make any difference once they figure it out. They work in pairs or more and just like predators from the last 350 million years they bite the arse end of the deer until it can't go any further then they go in for the kill.
They eat turkeys too.
I am in possession of a collection of old books. As in very old and probably should be in museum somewhere kinda old. A majority on hunting. A majority of those on Waterfowl. However, included are a couple real treasures written about hunting out west in the late 1800's and early 1900's. One is 1887. They are fascinating but difficult to read because they are not in our typical 4th Grade English. I have never seen a copy of these on the internet or elsewhere. EVER. Do not know of any others to be in existence and I look quite frequently for this type thing. The interest of that day was obviously reading about the exploits of the hunters, trappers and Indian Fighters and what it was like after you left Ft Smith Arkansas and ventured into the American West.
There are comments scattered throughout these 6-8 books on Coyotes. including descriptions of working pairs taking down "Deer". I would say that is likely Mule Deer. In the same books they would say the deer "hop". Some say they are grey, etc. but all refer to them as just "deer".
Animals don't evolve much in just 150 years. Pretty sure Coyotes.. they've always killed deer. Everyone just got brainwashed by the DCNR in the 1970's that claimed they didn't significantly impact the deer population. I personally think that was around the same time they were putting laws and regulations on people trapping. They didn't want to deal with canine trapping and having people get the neighbor's dogs caught, etc. so they claimed there was no reason to catch the coyotes they were harmless. That's my conspiracy theory. Now we are overrun with them.